Our water sources

If you do, then you might be surprised to learn that around half of Perth’s drinking water now comes from the sea via desalination, and the balance is from groundwater and recycled water. We still use dams, just not in the way you’d think.

Our changing climate means we don’t rely on rain for our drinking water anymore. And the water in our dams is no longer just made up of inflows from rain either. Water from other sources, particularly desalinated sea water, is stored in dams during periods of low demand, so that it’s there for when we need it most.

Our water cycle

The water cycle is a natural, continuous process that supports all life on Earth, and moves water throughout the Earth and its atmosphere. Perth’s water cycle is unique for our climate because we can’t rely on rain for our drinking water anymore.

Perth’s drinking water is a combination of water sourced from the sea and from underground aquifers. Sea water is piped into a desalination plant to have the salt removed, and groundwater is treated at one of our 82 water treatment plants. It then runs through a complex network of pipes to your home.

Once you’ve used this water it becomes wastewater, which is transferred from your home to one of our 100 wastewater treatment plants for initial treatment. Some water is then returned to the environment, and some is treated further so it’s good enough to drink before being recharged into our groundwater system. The process then starts all over again!

Our network

Ever stopped to think about how water gets to your tap?

The network of pipes delivering water to Perth, the Goldfields and Agricultural region and some parts of the South West is called The Integrated Water Supply Scheme (IWSS), and it’s the largest supply scheme we manage. It’s big…really big!

This network supplies over 361 billion litres of drinking water to more than 2 million people through 34,799 km of water pipes!

And it doesn’t end there because we then take away all of your used water too.

Wastewater mostly comes from sinks, showers and washing machines and we take away almost 450 million litres of it every day. Your used water enters 16,693 km of wastewater pipes before getting treated at a wastewater treatment plant.

Our changing climate

Our climate is changing, so where our water comes from, and how we use it is too.

The South West of Australia is said to have the fastest changing climate in the world yet our lifestyle is still oriented around water – pools, gardens and the beach. It’s a lifestyle that has an impact on our water supply.

So how are we going to make sure we’ve got enough, not just for now, but for later too?

Here’s the plan we’re working towards over the next 10 years, and we all play a part.

Help Perth households and businesses use even less water, and make greater use of recycled water.

Look at expanding our Groundwater Replenishment Scheme and further investigate other opportunities for reuse of treated wastewater.

Increase the capacity of our existing desalination plants, and investigate new desalination plants at Kwinana and Alkimos.

Expand our deep groundwater network.

Our groundwater

You’d be surprised at how reliant we are on the precious resource below our feet. Perth’s groundwater help make up the balance of our water supply and it’s under pressure due to climate change and increasing demand. But we can all make a difference.

Our groundwater also plays an important role in our environment, helping to keep our parks and ovals healthy and our ‘living things’ like lakes, wetlands and bushland, alive and well.

That’s why we all have a role to play in using water wisely, whether it’s drinking water or bore water.

Groundwater replenishment

Our changing climate means we need to secure climate-resilient water sources to continue to reduce our dependence on rain. One of these sources is groundwater replenishment.

This is where wastewater is treated to drinking water standards and then recharged into our groundwater supplies. The water then stays in our aquifers where it’s naturally filtered until needed. If that’s a shock to you, then here’s a thought: the amount of water on Earth never actually changes, so all our water is already naturally recycled in some way.

The great thing about this process is it doesn’t rely on rainfall and has the potential to recycle large volumes of water naturally and sustainably.

Water recycling

When water goes down the drain, it isn’t wasted - We recycle wastewater for other uses. And any that isn’t, enters the water cycle all over again.

Here are just a few of the ways we’re giving new life to water:

We recycle water for the environment. In the South West, the Swamphen, Island and Peninsula wetlands are enhanced with 30 million litres of treated wastewater each year from the Capel Wastewater Treatment Plant.

We supply recycled water for industry and business. The Kwinana Water Recycling Plant has been supplying high quality recycled water to the nearby industrial area since 2004 – which has resulted in a drop in drinking water use of more than 50% in the area!

We supply dual reticulation recycling schemes to some communities, which involves supplying water to customers from two sets of pipes – one for drinking water, and one for recycled water.

We recycle water for public open spaces. We’re involved in approximately 50 water recycling schemes across WA to irrigate parks, gardens, golf courses, sports grounds and other open spaces.

Councils

On the surface, councils may appear to use a lot of water. But in reality, they too have to sustainably manage their drinking water use and stick to their groundwater allocations.

Through our Waterwise Council Program, we’ve been supporting councils to implement innovative water efficiency initiatives within their own operations, to create liveable and resilient communities. Since 2009, over 80% of metro councils are participating in the Program, spreading the message to over 1.6 million of Perth’s residents.

Check out some of the work done by local councils to build waterwise communities for you and your family to enjoy.

City of Subiaco for example has redesigned their Mabel Talbot Reserve to include over 7,000 beautiful native plants, which thrive in our climate. An added benefit is carbon emissions & fertiliser use have been reduced, improving biodiversity in the park. But best of all, a 15% reduction in the Council’s drinking water use has been achieved.

Or City of Bayswater, who have a smart way of keeping their 190 parks, ovals and greenspaces functional, and waterwise at the same time. They use a centralised irrigation system that automatically switches off when rain is forecast – clever!

Businesses

Saving water is everyone’s business.

That’s why as part of our Waterwise Business Program, we’re working with over 316 business customers to reduce their water use through initiatives like water recycling, improved water efficiency and water-saving technology.

Businesses using more than 20,000kL of scheme water a year are required to submit a Water Efficiency Management Plan detailing targets to improve efficiency and planned water-saving actions and initiatives. They also need to provide annual progress reports so we can track them against their targets.

The program has helped businesses save over 83 billion litres of water so far!

Orange Sky

A shower, a clean and warm set of clothes, a friendly chat. They’re all simple things, but for the 9,500 people in WA experiencing homelessness, they’re sadly a luxury. Luckily, Orange Sky is here to help.

Orange Sky is a national charity using specially designed vans to give a free shower and laundry service to people doing it tough in Perth. WA’s first combined laundry and shower van called Lottie, is now operating in Perth, supported by Water Corporation and Lotterywest.

This initiative is a fantastic example of how precious water really is – even a small amount can make a truly enormous difference.